PHOENIX -- A very cold storm system will begin pushing its way through Arizona on Friday. The first impact of the storm will be on Thursday in northern Arizona. As the front approaches, we'll likely see wind gusts in the 40- to 50-mile-per-hour range by Thursday afternoon.

Friday, there's a high likelihood of snow in northern Arizona. Flagstaff could see between 3 and 7 inches of snow. There's also about a 30 percent chance for scattered rain showers around the Valley on Friday.

However, the really big story is going to be the prolonged cold weather that settles in. On Friday, daytime highs in the deserts will only be in the mid-50s. On Saturday, metro Phoenix will be in the upper 40s. But the worst of it will be during the nighttime and morning hours.

We're expecting Phoenix Sky Harbor International Airport to get below freezing for the first time in about two years beginning Saturday morning. That means some of the coldest Valley locations will be in the low 20s. Also, at this point, it looks like the morning cold won't break until Wednesday morning. As the forecast solidifies, look for the Weather Service to issue a Freeze Watch for this weekend by Wednesday afternoon.